Design of an Osteoinductive Extracellular Fibronectin Matrix Protein for Bone Tissue Engineering

Integrin-mediated cell-matrix interactions play an important role in osteogenesis. Here, we constructed a novel osteoinductive fibronectin matrix protein (oFN) for bone tissue engineering, designed to combine the integrin-binding modules from fibronectin (iFN) and a strong osteoinductive growth factor, bone morphogenetic protein-2. Compared with iFN, the purified oFN matrix protein caused a significant increase in cell adhesion and osteogenic differentiation of pre-osteoblast MC3T3-E1 cells (p < 0.05).     

Engineering of Self-Assembled Fibronectin Matrix Protein and Its Effects on Mesenchymal Stem Cells

Fibronectin (FN) contributes to cell adhesion, proliferation, and differentiation in various cell types. To enhance the activity of fibronectin at the sites of focal adhesion, we engineered a novel recombinant fibronectin (FNIII10) fragment connected to the peptide amphiphile sequence (PA), LLLLLLCCCGGDS. In this study, the effects of FNIII10-PA on rat mesenchymal stem cells (rMSCs) were compared with those of FNIII10. FNIII10-PA showed the prominent protein adhesion activity. In addition, FNIII10-PA showed a significantly higher effect on adhesion, proliferation, and differentiation of rMSCs than FNIII10. Taken together, the FNIII10-containing self-assembled sequence enhanced rMSCs adhesion, proliferation, and differentiation.     

Superstructure of yOTs-the network-based chemical process operator training system for multiple trainees

OTS (Operator Training System) is becoming popular for the safe and effective operation of chemical processes and control systems. This paper outlines the total hardware system superstructure and software modules of yOTS (Yonsei Operator Training System) which we developed. yOTS is a network based multi-training system composed of a workstation-based server module and PC-based user modules. The user module has a DCS-like user interface and sends data to OM (yOTS Manager) over the network. Reliability and stability are essential for the successful development of distributed OTS.State-of-the-art technologies of efficiency and stability are mainly considered in this paper. yOTS is superior to other OTS in its ease of handling discrete events, managing process models, expanding module functionality and multi-training over the network. The structure of yOTS and core algorithm for a multiple trainer over the network is also presented. A batch process example is used to illustrate the proposed advantages of yOTS.     

纳米磁流体在机械密封领域的研究现状及发展

简述磁流体在多领域的应用,说明磁流体与普通液体相比具有的特点和与传统密封相比具有的优点,论述磁流体在密封气体和液体方面的研究现状,指出磁流体在密封方面的发展趋势.     

Comparative properties of cakes prepared from rice flour and wheat flour

Received: 20 September 1999     

Synthesis and characterization of proton exchange poly (phenylenebenzophenone)s membranes grafted with propane sulfonic acid on pendant phenyl groups

A series of poly(phenylenebenzophenone)s with sulfonic acid groups via long alkyl side chains, SPPBPs, were successfully prepared as proton exchange membranes for fuel cells. The new monomer, 1,4-dichloro-2,5 diphenylenemethoxybenzophenone (PMBP) was synthesized by the Friedel–Crafts reaction of tetrachloroterephthalate with anisole and copolymerized with 1,4-dichloro-2,5-diphenylenebenzophenone (PBP) to prepare poly(phenylenebenzophenone)s copolymers containing dimethoxy groups (sPPMBP). After converting the methoxy group to the reactive hydroxyl group, the resulting side-chain-type sulfonated copolymers (SPPBP) were obtained by a sulfopropylation reaction. These SPPBP series membranes showed high proton conductivity in the range of 98.4–162.1 mS/cm 80 °C under 90% hydrated conditions. SPPBP-40 (IEC = 2.45 meq./g) showed comparable higher proton conductivity (162.1 mS/cm) than Nafion 211 (130.2 mS/cm) in the 90% hydrated state. The membranes were studied by ¹H NMR spectroscopy, thermo-gravimetric analysis, ionic exchange capacity, water uptake, and proton conductivity. Also surface morphologies were assessed by atomic force microscope (AFM).     

Using social media data to explore communication processes within South Korean online innovation communities

In order to explore new scientific and innovative communities, analyses based on a technological infrastructure and its related tools, for example, ‘Web of science’ database for Scientometric analysis, are necessary. However, there is little systematic documentation of social media data and webometric analysis in relation to Korean and broader Asian innovation communities. In this short communication, we present (1) webometric techniques to identify communication processes on the Internet, such as social media data collection and analysis using an API-based application; and (2) experimentation with new types of data visualization using NodeXL, such as social and semantic network analysis. Our research data is drawn from the social networking site, Twitter. We also examine the overlap between innovation communities in terms of their shared members, and then, (3) calculate entropy values for trilateral relationships.     

Comparative analysis of oxide phase formation and its effects on electrical properties of SiO2/InSb metal-oxide-semiconductor structures

We report on the changes in the interfacial phases between SiO₂ and InSb caused by various deposition temperatures and heat treatments. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy were used to evaluate the relative amount of each phase present at the interface. The effect of interfacial phases on the electrical properties of SiO₂/InSb metal-oxide-semiconductor (MOS) structures was investigated by capacitance-voltage (C-V) measurements. The amount of both In and Sb oxides increased with the deposition temperature. The amount of interfacial In oxide was larger for all samples, regardless of the deposition and annealing temperatures and times. In particular, the annealed samples contained less than half the amount of Sb oxide compared with the as-deposited samples, indicating a strong interfacial reaction between Sb oxide and the InSb substrate during annealing. The interface trap density sharply increased for deposition temperatures above 240 °C. The C-V measurements and Raman spectroscopy indicated that elemental Sb accumulation due to the interfacial reaction of Sb oxide with InSb substrate was responsible for the increased interfacial trap densities in these SiO₂/InSb MOS structures.